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Education: Student Outcomes |
Click here to search for other assets Effects of Temperature & Salinity on Density & Stratification (Steps 5-7) Grade levels: 5-8, 9-12 Theme: ocean circulation Activity: http://www.tos.org/hands-on/teaching_phys_concepts.pdf
Stratification forms an effective barrier for the exchange of nutrients and dissolved gases between the top, illuminated surface layer where phytoplankton can thrive, and the deep, nutrientrich waters. Stratification therefore has important implications for biological and biogeochemical processes in the ocean. For example, periods of increased ocean stratification have been associated with decreases in surface phytoplankton biomass. In coastal waters, prolonged periods of stratification can lead to hypoxia (low oxygen), causing mortality of fish, crabs, and other marine organisms. This activity compares warm and cold water, demonstrating that fluids arrange into layers according to their densities. Students in grades 9-12 should read the Background section (p. 4-5) of Chapter 1 (Density) in preparation for this activity. Videos
Flash Video | QuickTime MovieStudent Outcomes After completing this activity, students should be able to: Explain the effect of solar energy heat on ocean circulation. (O: 5-8) Explain the influence of ocean salinity on the thermohaline circulation (e.g., "global conveyor belt"). (O: 9-12) Key: C = climate / O = ocean circulation / T = 21st century technology / W = water cycle |